This study includes: (1) Continuation of research on the synthesis of ribo- and deoxyribo-oligonucleotide segments containing guanosine (G and dG), by means of the cyclic enediol pyrophosphate reagents. (2) Further studies on the effect of Mg2 plus ions on: (a) the conformation of oligonucleotides and tRNA tertiary structure; (b) the non-enzymatic and enzymatic reaction mechanisms of mono-, di- and triphosphates. (3) The mechanisms of phosphorylation by phosphomonoesters, XP (O) (OH)2, as a function of structure of X, state of ionization of the phosphate, and the nature of the medium, e.g., aprotic vs protic solvents.